1. Field of the Invention
The present invention relates to an exhaust gas sampling device for an outboard motor, designed to sample an exhaust gas from an engine through an exhaust gas sampling pipe.
2. Description of the Prior Art
Recently, in order to protect lake water from being stagnated or polluted, due to the exhaust gas discharged from an engine of an outboard motor, we are required to analyze harmful components contained in such exhaust gas.
Some exhaust gas sampling devices, for sampling exhaust gas through an exhaust gas sampling pipe provided in an exhaust gas passage, have been proposed (for example, see Japanese Patent Application Laid-open No. 121296/92).
The above prior art exhaust gas sampling device is mounted in the intermediate portion of an exhaust pipe. The exhaust gas sampling pipe extends horizontally through a wall of the exhaust pipe and through an extension case to the outside of the outboard motor. Thus, the exhaust gas can be sampled without removal of a cover for the outboard motor.
However, the prior art exhaust gas sampling device suffers from a problem that, if the exhaust gas sampling pipe is intended to be disposed to extend through both of the exhaust pipe and the extension case, as described above, openings in the exhaust pipe and extension case may not be aligned with each other, resulting in difficulty in mounting the exhaust gas sampling pipe.